ORGN 474 |
| Armando Córdova and Henrik Sundén. Department of Organic Chemistry, Stockholm University, The Arrhenius Laboratory, Stockholm, 106 91, Sweden |
| In this paper, we disclose the first proline-catalyzed direct catalytic asymmetric one-pot three-component cross-Mannich reaction. The highly chemoselective reactions between two different unmodified aldehydes and one aromatic amine are new routes to 3-amino aldehydes with dr >19:1 and up to >99% ee. The asymmetric cross-Mannich reactions are highly syn-selective and in several cases the two new carbon centers are formed with complete stereocontrol. The reaction does not display non-linear effects and therefore only one proline molecule is involved in the transition-state. The reaction was also catalyzed by other proline-derivatives with good selectivity. The Mannich products were converted to amino alcohols and 2-aminobutane-1, 4-diols with up to >99% ee. The one-pot three component direct catalytic asymmetric reactions were readily scaled-up, operationally simple and conducted in environmentally benign and wet solvents. The mechanism and stereochemistry of the proline-catalyzed one-pot three-component asymmetric cross-Mannich reaction are also discussed. |
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Total Synthesis, Asymmetric Reactions and Syntheses, Bioorganic
9:00 AM-11:00 AM, Wednesday, March 31, 2004 Anaheim Convention Center -- Hall C, Poster
Sci-Mix
Division of Organic Chemistry |